code: def test_default_attributes(monkeypatch):
      """Test the default attributes when no environment variables are set."""
      # calling these creates side effects in other tests
      if _XLA_GREATER_EQUAL_2_1:
          from torch_xla import runtime
  
          monkeypatch.setattr(runtime, "world_size", lambda: 2)
          monkeypatch.setattr(runtime, "global_ordinal", lambda: 0)
          monkeypatch.setattr(runtime, "local_ordinal", lambda: 0)
          monkeypatch.setattr(runtime, "host_index", lambda: 1)
      else:
          from torch_xla.experimental import pjrt
  
          monkeypatch.setattr(pjrt, "world_size", lambda: 2)
          monkeypatch.setattr(pjrt, "global_ordinal", lambda: 0)
          monkeypatch.setattr(pjrt, "local_ordinal", lambda: 0)
          os.environ["XRT_HOST_ORDINAL"] = "1"
  
      env = XLAEnvironment()
      assert not env.creates_processes_externally
      assert env.world_size() == 2
      assert env.global_rank() == 0
      assert env.local_rank() == 0
      assert env.node_rank() == 1
  
      with pytest.raises(NotImplementedError):
          _ = env.main_address
      with pytest.raises(NotImplementedError):
          _ = env.main_port
  
file_path: pytorch-lightning/tests/tests_fabric/plugins/environments/test_xla.py
imports: import os
  from unittest import mock
  import lightning.fabric
  import pytest
  from lightning.fabric.accelerators.xla import _XLA_GREATER_EQUAL_2_1
  from lightning.fabric.plugins.environments import XLAEnvironment
  from tests_fabric.helpers.runif import RunIf
label_desc: Use image node_id 1 for calling a global function with example usage: test_default_attributes(monkeypatch) without return types